Using electric pumps to drive a fluid, usually water, is known. Such pumps are used in washing machines or dishwashers, for example, to drain, at the end of a washing cycle, the water contained in the washing drum or tub out or towards a recirculation conduit that introduces said water back into the tub. In such pumps there are clearly two functional parts, the first refers to the part where the fluid is prepared so that it can be expelled through an expulsion element or impeller, and the second refers to the part where said element is made to rotate in order to allow driving said fluid.
Synchronous, preferably brushless, motors are normally used in such pumps, although asynchronous motors can also be used. A synchronous motor is a type of AC (alternating current) motor in which the rotation of the shaft of the rotor that moves the impeller is synchronized with the frequency of the supply current. The magnetic field required to make the shaft of the rotor rotate is generated by circulating an electric current through a coil arranged around the stator.
ES1101080 U discloses a drain pump comprising a pump body, in connection with the hydraulic part, and a motor body, in connection with the motorized part of the pump. The motor body comprises a rotor enclosure coupled to the pump body to close the pump at one end, an impeller arranged on one side of the rotor enclosure and a synchronous motor arranged on the other side of the rotor enclosure. The synchronous motor comprises a stator with a winding and a rotor with a shaft which is coupled to the impeller.